Photoelectric conversion element, imaging element, optical sensor, method for producing imaging element, and compound

Abstract

The present invention addresses the problem of providing a photoelectric conversion element having a low quantum efficiency dependency on magnetic field strength when green light is received. The photoelectric conversion element according to the present invention has, in the given order, a conductive film, a photoelectric conversion film, and a transparent conductive film, and the photoelectric conversion film contains a compound represented by formula (1).

Description

Photoelectric conversion element, imaging element, optical sensor, imaging element manufacturing method, compound

[0001] The present invention relates to a photoelectric conversion element, an imaging element, an optical sensor, a method for manufacturing an imaging element, and a compound.

[0002] In recent years, development of elements (e.g., imaging elements) having a photoelectric conversion film has progressed. For example, Patent Document 1 discloses a dye compound having a specific structure as a compound that can be applied to an organic photoelectric conversion layer of an organic image sensor or the like. Furthermore, Patent Document 2 discloses a dye compound having a specific structure that can be applied to an organic thin-film solar cell.

[0003] JP 2018-510845 A U.S. Patent Application Publication No. 2022 / 0135587

[0004] With the demand for improved performance of imaging devices, optical sensors, and the like, there is a demand for photoelectric conversion elements that exhibit excellent characteristics. One of the characteristics required for a photoelectric conversion element is that the quantum efficiency of the photoelectric conversion element is unlikely to decrease even when the electric field strength is changed, i.e., the quantum efficiency has a small electric field strength dependency. In response to this demand, the present inventors fabricated and examined photoelectric conversion elements containing the compounds disclosed in Patent Documents 1 and 2, and found that the electric field strength dependency of the quantum efficiency when receiving green and red light did not meet the desired level, and that there was room for improvement. The green and red light referred to above refers to light with a wavelength of 500 to 700 nm.

[0005] Therefore, an object of the present invention is to provide a photoelectric conversion element having a quantum efficiency that exhibits small dependence on electric field strength when receiving green and red light. Another object of the present invention is to provide an imaging element, an optical sensor, a method for manufacturing an imaging element, and a compound related to the photoelectric conversion element.

[0006] As a result of extensive research into solving the above problems, the present inventors have found that the problems can be solved by the following configuration.

[0007] [1] A photoelectric conversion element having a conductive film, a photoelectric conversion film, and a transparent conductive film in this order, wherein the photoelectric conversion film contains a compound represented by formula (1) described below. １ and A２ [3] The photoelectric conversion element according to [1], wherein X each independently represents a group represented by the above formula (A-1). ３ [4] The photoelectric conversion element according to [1] or [2], wherein Y represents a sulfur atom. １ ~Y ４ are each independently -CR Ｙ１ [5] The photoelectric conversion element according to any one of [1] to [3], wherein X represents １ and X ２ are each independently -NR Ｘ１ -, -CR Ｘ２ R Ｘ３ - or -SiR Ｘ４ R Ｘ５ -. [6] The photoelectric conversion element according to any one of [1] to [4], wherein the photoelectric conversion film further contains an n-type organic semiconductor, and the photoelectric conversion film has a bulk heterostructure formed by mixing the compound represented by formula (1) with the n-type organic semiconductor. [7] The photoelectric conversion element according to [6], wherein the n-type organic semiconductor contains a fullerene selected from the group consisting of fullerenes and derivatives thereof. [8] The photoelectric conversion element according to any one of [1] to [7], wherein the photoelectric conversion film further contains a p-type organic semiconductor. [9] The photoelectric conversion element according to any one of [1] to [8], wherein the photoelectric conversion film further contains a dye.

[10] The photoelectric conversion element according to any one of [1] to [9], wherein one or more intermediate layers are provided between the conductive film and the transparent conductive film in addition to the photoelectric conversion film.

[11] An imaging element having the photoelectric conversion element according to any one of [1] to

[10] .

[12] An optical sensor having the photoelectric conversion element according to any one of [1] to

[10] .

[13] A method for manufacturing an imaging element, comprising a step of manufacturing the photoelectric conversion element according to any one of [1] to

[10] .

[14] A compound represented by formula (1) described later.

[15] A １ and A ２

[16] The compound according to

[14] , wherein X each independently represents a group represented by the above formula (A-1). ３

[17] The compound according to

[14] or

[15] , wherein Y represents a sulfur atom. １ ~Y ４ are each independently -CR Ｙ１

[18] The compound according to any one of

[14] to

[16] , wherein X represents １ and X ２ are each independently -NR Ｘ１ -, -CR Ｘ２ R Ｘ３ - or -SiR Ｘ４ R Ｘ５ The compound according to any one of

[14] to

[17] , wherein - represents.

[0008] According to the present invention, a photoelectric conversion element having a quantum efficiency that exhibits small dependence on electric field strength when receiving green and red light can be provided. The present invention also provides an imaging element, an optical sensor, a method for manufacturing an imaging element, and a compound related to the photoelectric conversion element.

[0009] 1 is a schematic cross-sectional view showing an example of the configuration of a photoelectric conversion element.

[0010] The present invention will be described in detail below. The following description of the components may be based on representative embodiments of the present invention, but the present invention is not limited to such embodiments.

[0011] In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits.

[0012] In this specification, a hydrogen atom may be either a protist atom (a normal hydrogen atom) or a deuterium atom (for example, a deuterium atom). In this specification, when there are multiple substituents, linking groups, etc. (hereinafter also referred to as "substituents, etc.") represented by a specific symbol, or when multiple substituents, etc. are specified at the same time, this means that the respective substituents, etc. may be the same or different from each other. This also applies to the specification of the number of substituents, etc.

[0013] In this specification, unless otherwise specified, examples of the "substituent" include the groups exemplified as the substituent W below.

[0014] (Substituent W) The substituent W in this specification will be described. Examples of the substituent W include a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), an alkyl group (including a cycloalkyl group, a bicycloalkyl group, and a tricycloalkyl group), an alkenyl group (including a cycloalkenyl group and a bicycloalkenyl group), an alkynyl group, an aryl group, a heterocyclic group (a heteroaryl group or an aliphatic heterocyclic group), a cyano group, a nitro group, an alkoxy group, an aryloxy group, a silyl group, a silyloxy group, a heterocyclic oxy group, an acyloxy group, a carbamoyloxy group, an alkoxycarbonyloxy group, an aryl ... Examples of substituents include an alkyloxy group, a primary, secondary, or tertiary amino group (including an anilino group), an alkylthio group, an arylthio group, a heterocyclic thio group, an alkyl or arylsulfinyl group, an alkyl or arylsulfonyl group, an acyl group, an aryloxycarbonyl group, an alkoxycarbonyl group, an aryl or heterocyclic azo group, an imido group, a phosphino group, a phosphinyl group, a phosphinyloxy group, a phosphinylamino group, a phosphono group, a carboxy group, a phosphate group, a sulfonic acid group, a hydroxy group, a thiol group, an acylamino group, a carbamoyl group, a ureido group, and a boronic acid group. Each of the above groups may further have a substituent (e.g., one or more of the above groups) if possible. For example, an alkyl group which may have a substituent is also included as one form of the substituent W. When the substituent W has a carbon atom, the number of carbon atoms contained in the substituent W is, for example, 1 to 20. The number of atoms other than hydrogen atoms contained in the substituent W is, for example, 1 to 30. The specific compounds described below may have, as substituents, a carboxy group, a salt of a carboxy group, a phosphate group, a salt of a phosphate group, a sulfonic acid group, a salt of a sulfonic acid group, a hydroxy group, a thiol group, an acylamino group, a carbamoyl group, a ureido group, a boronic acid group (-B(OH) ２ ) and / or does not have a primary amino group.

[0015] In this specification, examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0016] In this specification, unless otherwise specified, the aliphatic hydrocarbon group may be linear, branched, or cyclic. Examples of the aliphatic hydrocarbon group include an alkyl group, an alkenyl group, and an alkynyl group. In this specification, unless otherwise specified, the number of carbon atoms in the alkyl group is preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 6. Unless otherwise specified, the alkyl group may be linear, branched, or cyclic. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-hexyl group, a cyclopropyl group, and a cyclopentyl group. The cyclic alkyl group may be a cycloalkyl group, a bicycloalkyl group, or a tricycloalkyl group, and the alkyl group may have these ring structures as partial structures. In the alkyl group that may have a substituent, examples of the substituent that the alkyl group may have include the groups exemplified for the substituent W. Of these, an aryl group (preferably having 6 to 18 carbon atoms, more preferably having 6 carbon atoms), a heteroaryl group (preferably having 5 to 18 carbon atoms, more preferably having 5 to 6 carbon atoms), or a halogen atom (preferably a fluorine atom or a chlorine atom) is preferred.

[0017] In this specification, unless otherwise specified, the alkyl group moiety in the alkoxy group and alkylthio group is preferably the above-mentioned alkyl group. In the alkoxy group which may have a substituent, examples of the substituent that the alkoxy group may have include the same as the substituent in the alkyl group which may have a substituent. In the alkylthio group which may have a substituent, examples of the substituent that the alkylthio group may have include the same as the substituent in the alkyl group which may have a substituent.

[0018] In this specification, unless otherwise specified, the alkenyl group may be linear, branched, or cyclic. The number of carbon atoms in the alkenyl group is preferably 2 to 20. In the alkenyl group which may have a substituent, examples of the substituent that the alkenyl group may have include the same as the substituents in the alkyl group which may have a substituent. In this specification, unless otherwise specified, the alkynyl group may be linear, branched, or cyclic. The number of carbon atoms in the alkynyl group is preferably 2 to 20. In the alkynyl group which may have a substituent, examples of the substituent that the alkynyl group may have include the same as the substituents in the alkyl group which may have a substituent.

[0019] In this specification, unless otherwise specified, an aromatic ring or an aromatic ring constituting an aromatic ring group may be either a monocyclic ring or a polycyclic ring (e.g., 2 to 6 rings). A monocyclic aromatic ring is an aromatic ring having only one aromatic ring structure as a ring structure. A polycyclic (e.g., 2 to 6 rings) aromatic ring is an aromatic ring having a plurality of (e.g., 2 to 6) condensed aromatic ring structures as a ring structure. The number of ring members in the aromatic ring is preferably 5 to 15. In this specification, unless otherwise specified, an aromatic ring may be either an aromatic hydrocarbon ring or an aromatic heterocyclic ring. When the aromatic ring is an aromatic heterocyclic ring, the number of heteroatoms contained as ring member atoms is, for example, 1 to 10. Examples of the heteroatom include a nitrogen atom, a sulfur atom, an oxygen atom, a selenium atom, a tellurium atom, a phosphorus atom, a silicon atom, and a boron atom. Examples of the aromatic hydrocarbon ring include a benzene ring, a naphthalene ring, an anthracene ring, a pyrene ring, a phenanthrene ring, and a fluorene ring.Examples of the aromatic heterocycle include a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, a triazine ring (e.g., a 1,2,3-triazine ring, a 1,2,4-triazine ring, and a 1,3,5-triazine ring), a tetrazine ring (e.g., a 1,2,4,5-tetrazine ring), a quinoxaline ring, a pyrrole ring, a furan ring, a thiophene ring, an imidazole ring, an oxazole ring, a thiazole ring, a benzopyrrole ring, a benzofuran ring, a benzothiophene ring, a benzimidazole ring, a benzoxazole ring, a benzothiazole ring, a naphthopyrrole ring, a naphthofuran ring, a naphthothiophene ring, a naphthoimidazole ring, a naphthoxazole ring, a pyrroloimidazole ring (e.g., a 5H-pyrrolo[1,2-a]imidazole ring), an imidazooxazole ring (e.g., an imidazo[2,1-b]oxazole ring), Thienothiazole rings (for example, thieno[2,3-d]thiazole rings, etc.), benzothiadiazole rings, benzodithiophene rings (for example, benzo[1,2-b:4,5-b']dithiophene rings, etc.), thienothiophene rings (for example, thieno[3,2-b]thiophene rings, etc.), thiazolothiazole rings (for example, thiazolo[5,4-d]thiazole rings, etc.), naphthodithiophene rings (for example, naphtho[2,3- b:6,7-b']dithiophene ring, naphtho[2,1-b:6,5-b']dithiophene ring, naphtho[1,2-b:5,6-b']dithiophene ring, and 1,8-dithiadicyclopenta[b,g]naphthalene ring, etc.), benzothienobenzothiophene ring, dithieno[3,2-b:2',3'-d]thiophene ring, and 3,4,7,8-tetrathiadicyclopenta[a,e]pentalene ring.

[0020] In this specification, the term "aromatic ring group" includes, for example, a group obtained by removing one or more (e.g., 1 to 5, etc.) hydrogen atoms from the above-mentioned aromatic ring. In this specification, the term "aromatic hydrocarbon group" includes, for example, a group obtained by removing one or more (e.g., 1 to 5, etc.) hydrogen atoms from the above-mentioned aromatic hydrocarbon ring, and the term "aromatic heterocyclic group" includes, for example, a group obtained by removing one or more (e.g., 1 to 5, etc.) hydrogen atoms from the above-mentioned aromatic heterocycle. In this specification, the term "aryl group" includes, for example, a group obtained by removing one hydrogen atom from a ring corresponding to the aromatic hydrocarbon ring of the above-mentioned aromatic ring. In this specification, the term "heteroaryl group" includes, for example, a group obtained by removing one hydrogen atom from a ring corresponding to the aromatic heterocycle of the above-mentioned aromatic ring. In this specification, the term "arylene group" includes, for example, a group obtained by removing two hydrogen atoms from a ring corresponding to the aromatic hydrocarbon ring of the above-mentioned aromatic ring. In this specification, the term "heteroarylene group" refers to, for example, a group obtained by removing two hydrogen atoms from a ring corresponding to an aromatic heterocycle among the above-mentioned aromatic rings. In the optionally substituted aromatic ring group, optionally substituted aryl group, optionally substituted heteroaryl group, optionally substituted arylene group, and optionally substituted heteroarylene group, the types of substituents that these groups may have include, for example, the groups exemplified for the substituent W. When these groups have substituents, the number of substituents may be 1 or more (for example, 1 to 4, etc.).

[0021] As used herein, the term "non-aromatic ring" refers to a ring structure that does not fall under the category of aromatic rings, and examples thereof include aliphatic hydrocarbon rings and aliphatic heterocycles. Examples of the aliphatic hydrocarbon ring include cycloalkanes, cycloalkenes, and cycloalkynes. Examples of the aliphatic heterocycle include a pyrrolidine ring, oxolane ring, thiolane ring, piperidine ring, tetrahydropyran ring, thiane ring, piperazine ring, morpholine ring, quinuclidine ring, azetidine ring, oxetane ring, aziridine ring, dioxane ring, and γ-butyrolactone ring. As used herein, the term "aliphatic hydrocarbon ring group" refers to, for example, a group obtained by removing one or more hydrogen atoms (e.g., 1 to 5, etc.) from a ring that falls under the category of an aliphatic hydrocarbon ring. As used herein, the term "aliphatic heterocyclic group" refers to, for example, a group obtained by removing one or more hydrogen atoms (e.g., 1 to 5, etc.) from a ring that falls under the category of an aliphatic heterocycle.

[0022] In this specification, when a formula showing a chemical structure contains a plurality of identical symbols indicating the type or number of groups, the contents of the plurality of identical symbols are independent of each other, and the contents of the plurality of identical symbols may be the same or different, unless otherwise specified. In this specification, when a formula showing a chemical structure contains a plurality of groups of the same type (e.g., alkyl groups, etc.), the specific contents of the plurality of groups of the same type are independent of each other, and the specific contents of the plurality of groups of the same type may be the same or different, unless otherwise specified.

[0023] In this specification, the bonding direction of a divalent group (e.g., -CO-O-, etc.) is not limited unless otherwise specified. For example, when Y is -CO-O- in a compound represented by the formula "X-Y-Z," the compound may be either "X-O-CO-Z" or "X-CO-O-Z."

[0024] In this specification, with respect to compounds that may have geometric isomers (cis-trans isomers), the general formula or structural formula representing the compound may be described in only one of the cis and trans forms for convenience. Even in such cases, unless otherwise specified, the form of the compound is not limited to either the cis or trans form, and the compound may be in either the cis or trans form. Furthermore, in this specification, with respect to compounds having an asymmetric atom, the general formula or structural formula representing the compound may be described without distinguishing between stereoisomers for convenience. Even in such cases, unless otherwise specified, the form of the compound is not limited to either form, and may be any one form or a mixture. For example, a compound having an asymmetric carbon atom may be either the S-form or the R-form, or a mixture thereof, unless otherwise specified.

[0025] In this specification, unless otherwise specified, * in a formula indicates a bonding position.

[0026] [Photoelectric conversion element] The photoelectric conversion element of the present invention is a photoelectric conversion element having a conductive film, a photoelectric conversion film, and a transparent conductive film in this order, and the photoelectric conversion film contains a compound represented by formula (1) (hereinafter also referred to as a "specific compound").

[0027] Although the reason why the photoelectric conversion element having the above configuration can solve the problems of the present invention is not entirely clear, the inventors speculate as follows. The following speculation does not limit the mechanism by which the effect is obtained. In other words, even if the effect is obtained by a mechanism other than the one described below, it is still within the scope of the present invention. The specific compound is a so-called ADA-type dye compound having a donor moiety (D) and an acceptor moiety (A). Such dye compounds tend to have high aggregation due to their conjugated structure. The donor moiety of the specific compound of the present invention has a structure in which a 6-membered ring is fused to the end of a fused ring consisting of three 5-membered rings, and the symmetry is appropriately adjusted. The specific compound formed by combining such a donor moiety with a specific acceptor suppresses excessive aggregation in the photoelectric conversion film, thereby achieving efficient charge separation even at low electric field strength. As a result, it is believed that charges can move efficiently even at low electric field strength, i.e., the quantum efficiency of the photoelectric conversion element has little dependence on electric field strength. Hereinafter, a smaller dependency of the quantum efficiency on the electric field strength when receiving green and red light will also be referred to as "a more excellent effect of the present invention."

[0028] FIG. 1 shows a cross-sectional schematic diagram of one embodiment of the photoelectric conversion element of the present invention. The photoelectric conversion element 10a shown in FIG. 1 has a configuration in which a conductive film (hereinafter also referred to as the "lower electrode") 11 functioning as a lower electrode, an electron blocking film 16A, a photoelectric conversion film 12 containing a specific compound, and a transparent conductive film (hereinafter also referred to as the "upper electrode") 15 functioning as an upper electrode are stacked in this order. FIG. 2 shows an example of the configuration of another photoelectric conversion element. The photoelectric conversion element 10b shown in FIG. 2 has a configuration in which an electron blocking film 16A, a photoelectric conversion film 12, a hole blocking film 16B, and an upper electrode 15 are stacked in this order on a lower electrode 11. Note that the stacking order of the electron blocking film 16A, the photoelectric conversion film 12, and the hole blocking film 16B in FIGS. 1 and 2 may be changed as appropriate depending on the application and characteristics.

[0029] In the photoelectric conversion element 10a (or 10b), it is preferable that light is incident on the photoelectric conversion film 12 through the upper electrode 15. When the photoelectric conversion element 10a (or 10b) is used, a voltage can be applied. In this case, the lower electrode 11 and the upper electrode 15 form a pair of electrodes, and a voltage of 1×10 is applied between the pair of electrodes. －５ ~1 x 10 ７ In terms of performance and power consumption, it is preferable to apply a voltage of 1×10 V / cm. －４ ~1 x 10 ７ V / cm is more preferable, and 1×10 －３ ~5 x 10 ６ V / cm is more preferable. Regarding the voltage application method, it is preferable to apply the voltage so that the electron blocking film 16A side serves as the cathode and the photoelectric conversion film 12 side serves as the anode in FIGS. 1 and 2. When the photoelectric conversion element 10a (or 10b) is used as a photosensor or incorporated into an imaging element, a voltage can be applied in a similar manner. As will be described in detail later, the photoelectric conversion element 10a (or 10b) can be suitably used as an imaging element. The configuration of each layer constituting the photoelectric conversion element of the present invention will be described in detail below.

[0030] [Photoelectric Conversion Film] The photoelectric conversion element has a photoelectric conversion film.

[0031] <Specific Compound> The photoelectric conversion film contains a specific compound, which is a compound represented by formula (1).

[0032]

[0033] In formula (1), X １ and X ２ each independently represents a sulfur atom, an oxygen atom, a selenium atom, or —NR Ｘ１ -, -CR Ｘ２ R Ｘ３ -, -SiR Ｘ４ R Ｘ５ - or -GeR Ｘ６ R Ｘ７ - represents X ３ represents a sulfur atom, an oxygen atom, a selenium atom, or —NR Ｘ１ - represents. Ｘ１ ~R Ｘ７R each independently represents a hydrogen atom or a substituent. Ｘ２ and R Ｘ３ , R Ｘ４ and R Ｘ５ , and R Ｘ６ and R Ｘ７ may be bonded to each other to form a ring which may have a substituent. １ ~Y ４ are each independently -CR Ｙ１ = or represents a nitrogen atom. Ｙ１ represents a hydrogen atom or a substituent. １ and R ２ each independently represents a hydrogen atom or a substituent. １ and A ２ each independently represents a group represented by formula (A-1) or a group represented by formula (A-2). １ represents a ring containing two or more carbon atoms and which may have a substituent. １ represents a sulfur atom, an oxygen atom, and ═NR Ｗ１ , or =CR Ｗ２ R Ｗ３ Represents R Ｗ１ represents a hydrogen atom or a substituent. Ｗ２ and R Ｗ３ each independently represents a cyano group, —SO ２ R Ｗ４ , -COOR Ｗ５ , or -COR Ｗ６ Represents R Ｗ４ ~R Ｗ６ each independently represents an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, or an aliphatic heterocyclic group which may have a substituent. * represents a bonding position. In formula (A-2), R Ａ１ and R Ａ２ each independently represents a cyano group, —SO ２ R Ｚ１ , -COOR Ｚ２ , or -COR Ｚ３ Represents R Ｚ１ ~R Ｚ３each independently represents an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, or an aliphatic heterocyclic group which may have a substituent. * represents a bonding position.

[0034] In formula (1), X １ and X ２ each independently represents a sulfur atom, an oxygen atom, a selenium atom, or —NR Ｘ１ -, -CR Ｘ２ R Ｘ３ -, -SiR Ｘ４ R Ｘ５ - or -GeR Ｘ６ R Ｘ７ -NR Ｘ１ -, -CR Ｘ２ R Ｘ３ - or -SiR Ｘ４ R Ｘ５ - is preferred.

[0035] R Ｘ１ ~R Ｘ７ R each independently represents a hydrogen atom or a substituent, and is preferably a substituent. Ｘ１ ~R Ｘ７ Examples of the substituent represented by the formula (I) include the substituents exemplified for the substituent W described above, and in terms of the effects of the present invention being more excellent, an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, or an aliphatic heterocyclic group which may have a substituent is preferred, an aliphatic hydrocarbon group which may have a substituent or an aromatic ring group which may have a substituent is more preferred, and an aliphatic hydrocarbon group which may have a substituent is even more preferred.

[0036] The aliphatic hydrocarbon group may be linear, branched, or cyclic. Examples of the aliphatic hydrocarbon group include alkyl groups, alkenyl groups, and alkynyl groups, with alkyl groups being preferred. The linear aliphatic hydrocarbon group preferably has 1 to 20 carbon atoms, more preferably 1 to 10, even more preferably 1 to 4, and particularly preferably 1 or 2. The branched aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 10, even more preferably 3 to 7, and particularly preferably 3 to 5. The cyclic aliphatic hydrocarbon group may be either monocyclic or polycyclic. The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 10, and even more preferably 3 to 6.

[0037] The aromatic ring group may be either an aromatic hydrocarbon group or an aromatic heterocyclic group. The aromatic ring group may be either monocyclic or polycyclic, with a monocyclic group being preferred. The number of ring atoms in the aromatic ring group is preferably 5 to 18, more preferably 5 to 10, and even more preferably 5 to 8. The definition and specific examples of the aromatic hydrocarbon group are as described above, with a phenyl group or naphthyl group being preferred, and a phenyl group being more preferred. Examples of heteroatoms contained in the aromatic heterocyclic group include sulfur atoms, oxygen atoms, nitrogen atoms, selenium atoms, tellurium atoms, phosphorus atoms, silicon atoms, and boron atoms, with sulfur atoms, oxygen atoms, or nitrogen atoms being preferred. The definition and specific examples of the aromatic heterocyclic group are as described above, with a thiophene ring group, a furan ring group, or a pyridine ring group being preferred. The aromatic ring group may have a substituent, as described above. When the aromatic ring group has a substituent, the number of substituents is not particularly limited, but is preferably 1 to 3.

[0038] The aliphatic heterocyclic group may be either monocyclic or polycyclic, with monocyclic being preferred. The number of ring atoms in the aliphatic heterocyclic group is preferably 3 to 18, more preferably 5 to 10, and even more preferably 5 to 8. Examples of heteroatoms contained in the aliphatic heterocyclic group include sulfur, oxygen, nitrogen, selenium, tellurium, phosphorus, silicon, and boron atoms, with sulfur, oxygen, or nitrogen being preferred. The definition and specific examples of the aliphatic heterocyclic group are as described above, with a thiolane ring group, piperidine ring group, tetrahydrofuran ring group, or tetrahydropyran ring group being preferred. The aliphatic heterocyclic group may have a substituent, as described above. When the aliphatic heterocyclic group has a substituent, the number of substituents is not particularly limited, but is preferably 1 to 3.

[0039] Examples of the substituent that the aliphatic hydrocarbon group, aromatic ring group, and aliphatic heterocyclic group may have include the substituents exemplified for the substituent W described above, and a substituent selected from the substituent group S described below is preferred.

[0040] R Ｘ２ and R Ｘ３ , R Ｘ４ and R Ｘ５ , and R Ｘ６ and R Ｘ７ may be bonded to each other to form a ring which may have a substituent. Ｘ２ and R Ｘ３ may be bonded to each other to form a ring which may have a substituent, R Ｘ４ and R Ｘ５ may be bonded to each other to form a ring which may have a substituent, R Ｘ６ and R Ｘ７may be bonded to each other to form a ring which may have a substituent. The ring may be either an aromatic ring or a non-aromatic ring, and may be either a monocyclic ring or a polycyclic ring. The ring may have a heteroatom. Examples of the heteroatom include a nitrogen atom, a sulfur atom, an oxygen atom, a selenium atom, a tellurium atom, a phosphorus atom, a silicon atom, and a boron atom, with a sulfur atom, a nitrogen atom, or an oxygen atom being preferred. The number of ring members in the ring is preferably 3 to 20, more preferably 5 to 12. Examples of the substituent which the ring may have include the substituents exemplified for the substituent W above, with a substituent selected from the substituent group S described below being preferred.

[0041] In formula (1), X ３ represents a sulfur atom, an oxygen atom, a selenium atom, or —NR Ｘ１ R represents -, and a sulfur atom is preferred in terms of a superior response speed. Ｘ１ The details are as described above.

[0042] In formula (1), Y １ ~Y ４ are each independently -CR Ｙ１ = or a nitrogen atom. In terms of the effects of the present invention being more excellent, Y １ ~Y ４ Three or more of the above are -CR Ｙ１ Preferably, Y represents １ ~Y ４ Ga-CR Ｙ１ It is more preferable to represent =.

[0043] R Ｙ１ represents a hydrogen atom or a substituent. Ｙ１Examples of the substituent represented by the formula (I) include the substituents exemplified for the substituent W described above. In terms of better effects of the present invention, an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, an aliphatic heterocyclic group which may have a substituent, a silyl group, a halogen atom, a cyano group, a nitro group, an acyl group, an alkoxy group, or an aryloxy group is preferred, an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, an aliphatic heterocyclic group which may have a substituent, a silyl group, or a halogen atom is more preferred, and an aliphatic hydrocarbon group which may have a substituent or a halogen atom is even more preferred.

[0044] R Ｙ１ The definitions and preferred embodiments of the optionally substituted aliphatic hydrocarbon group, the optionally substituted aromatic ring group, and the optionally substituted aliphatic heterocyclic group represented by the following formula (I) are as follows: Ｘ１ ~R Ｘ７ These are the same as the groups exemplified as the substituent represented by the formula:

[0045] The silyl group is —SiR Ｓｉ ３ R is a group represented by the formula: Ｓｉ R each independently represents an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, or an aliphatic heterocyclic group which may have a substituent. Ｓｉ The definitions and preferred embodiments of the optionally substituted aliphatic hydrocarbon group, the optionally substituted aromatic ring group, and the optionally substituted aliphatic heterocyclic group represented by the following formula (I) are as follows: Ｘ１ ~R Ｘ７ These are the same as the groups exemplified as the substituent represented by the formula:

[0046] The halogen atom includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom or a chlorine atom being preferred.

[0047] The hydrocarbon group contained in the acyl group may be either an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and an aliphatic hydrocarbon group is preferred. A preferred embodiment of the aliphatic hydrocarbon group and aromatic hydrocarbon group contained in the acyl group is R Ｘ１ ~R Ｘ７The acyl group preferably has 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, and even more preferably 2 to 6 carbon atoms.

[0048] The alkyl group of the alkoxy group may be linear, branched, or cyclic. The alkoxy group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, still more preferably 1 to 5 carbon atoms, and particularly preferably 1 to 3 carbon atoms.

[0049] The aryl group in the aryloxy group may be either monocyclic or polycyclic, preferably monocyclic, and preferably has 5 to 18 carbon atoms, more preferably 6 to 10 carbon atoms, and even more preferably 6 to 8 carbon atoms.

[0050] The above R Ｙ１ Examples of the substituent that may be possessed by each group represented by the following formula (I) include the substituents exemplified for the substituent W described above, and a substituent selected from the substituent group S is preferred.

[0051] Substituent group S will be described in detail. Substituent group S: linear aliphatic hydrocarbon groups having 1 to 3 carbon atoms, branched aliphatic hydrocarbon groups having 3 to 7 carbon atoms, cyclic aliphatic hydrocarbon groups having 3 to 6 carbon atoms, aromatic ring groups having 5 to 12 ring atoms which may have a substituent, alkoxy groups having 1 to 5 carbon atoms, acyl groups having 2 to 6 carbon atoms, silyl groups, and halogen atoms.

[0052] The number of carbon atoms in the linear aliphatic hydrocarbon group in the above-mentioned substituent group S is 1 to 3, and preferably 1 or 2. The number of carbon atoms in the branched aliphatic hydrocarbon group in the above-mentioned substituent group S is 3 to 7, and preferably 3 or 4. The cyclic aliphatic hydrocarbon group in the above-mentioned substituent group S is preferably monocyclic.

[0053] The aromatic ring group in the substituent group S may be either a monocyclic or polycyclic ring, with a monocyclic ring being preferred. The aromatic ring group may be either an aromatic hydrocarbon group or an aromatic heterocyclic group, with an aromatic hydrocarbon group being preferred. The heteroatom contained in the aromatic heterocyclic group is preferably an oxygen atom, a nitrogen atom, or a sulfur atom. The number of ring atoms in the aromatic ring group is 5 to 12, preferably 5 to 10, and more preferably 5 or 6. Examples of the substituent that the aromatic ring group may have include the substituents exemplified for the substituent W described above. A substituent selected from the substituent group S is preferred, and a linear aliphatic hydrocarbon group having 1 to 3 carbon atoms, a branched aliphatic hydrocarbon group having 3 to 7 carbon atoms, a silyl group, an alkoxy group having 1 to 5 carbon atoms, or a halogen atom is more preferred. When the aromatic ring group has a substituent, the number of substituents is preferably 1 to 3.

[0054] The number of carbon atoms in the alkoxy group in the above-mentioned Substituent Group S is 1 to 5, more preferably 1 to 4, and still more preferably 1 or 2. The number of carbon atoms in the acyl group in the above-mentioned Substituent Group S is 2 to 6, preferably 2 to 5, and more preferably 2 or 3.

[0055] The definition and preferred embodiments of the silyl group in the above-mentioned substituent group S are as follows: Ｙ１ Among them, the silyl group represented by R Ｓｉ each independently represents a linear aliphatic hydrocarbon group having 1 to 3 carbon atoms, a branched aliphatic hydrocarbon group having 3 to 7 carbon atoms, a cyclic aliphatic hydrocarbon group having 3 to 6 carbon atoms, or an aromatic ring group having 5 to 12 ring atoms which may have a substituent; Ｓｉ ３ A group represented by the following formula is preferred.

[0056] Examples of the halogen atom in the above-mentioned substituent group S include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom or a chlorine atom is preferred.

[0057] In formula (1), R １ and R ２ R each independently represents a hydrogen atom or a substituent. １ and R ２Examples of the substituent represented by the formula (I) include the substituents exemplified for the substituent W described above, and a hydrogen atom is preferred in that the effects of the present invention are more excellent.

[0058] In formula (1), A １ and A ２ each independently represents a group represented by formula (A-1) or a group represented by formula (A-2), and the group represented by formula (A-1) is preferred in terms of more excellent quantum efficiency.

[0059]

[0060] In formula (A-1), C １ represents a ring containing two or more carbon atoms and which may have a substituent. １ The two carbon atoms contained in are the two carbon atoms specified in formula (A-1). The number of carbon atoms in the ring is preferably 3 to 30, more preferably 3 to 20, and even more preferably 3 to 10. The number of carbon atoms in the ring is the number including the two carbon atoms specified in the formula. The ring may be either an aromatic ring or a non-aromatic ring. The ring may be either a monocyclic or polycyclic ring, and is preferably a 5-membered ring, a 6-membered ring, or a fused ring containing at least one of a 5-membered ring and a 6-membered ring. The number of carbon atoms in the fused ring containing at least one of a 5-membered ring and a 6-membered ring is preferably 6 to 20, more preferably 6 to 15, and even more preferably 8 to 10. The ring may have a heteroatom. Examples of the heteroatom include a nitrogen atom, a sulfur atom, an oxygen atom, a selenium atom, a tellurium atom, a phosphorus atom, a silicon atom, and a boron atom, and a sulfur atom, a nitrogen atom, or an oxygen atom is preferred. The number of heteroatoms in the ring is preferably 0 to 10, and more preferably 0 to 5. １ Among the carbon atoms constituting the ring represented by the formula (A-1), the carbon atom at the bonding position marked with * and W １ Carbon atoms other than the carbon atom bonded to may be substituted with a carbonyl carbon (>C=O) or a thiocarbonyl carbon (>C=S), or the like.

[0061] Examples of the substituent that the ring may have include the groups exemplified for the substituent W above, and are preferably a halogen atom, an alkyl group which may have a substituent, an aromatic ring group which may have a substituent, or a silyl group, and more preferably a halogen atom or an alkyl group. The alkyl group may be linear, branched, or cyclic, and is preferably linear. The alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 3 carbon atoms. The substituent that the alkyl group may have is preferably a halogen atom, an aromatic ring group, or a silyl group. The substituent that the aromatic ring group may have is preferably a halogen atom, an alkyl group, or a silyl group.

[0062] The ring represented by formula (A-1) is preferably a ring used as an acidic nucleus (for example, an acidic nucleus in a merocyanine dye), and examples thereof include the following nuclei: (a) 1,3-dicarbonyl nucleus: for example, a 1,3-indandione nucleus, 1,3-cyclohexanedione, 5,5-dimethyl-1,3-cyclohexanedione, and 1,3-dioxane-4,6-dione; (b) pyrazolinone nucleus: for example, 1-phenyl-2-pyrazolin-5-one, 3-methyl-1-phenyl-2-pyrazolin-5-one, and 1-(2-benzothiazolyl)-3-methyl-2-pyrazolin-5-one; (c) isoxazolinone nucleus: for example, 3-phenyl-2-isoxazolin-5-one and 3-methyl-2-isoxazolin-5-one; (d) Oxindole nucleus: For example, 1-alkyl-2,3-dihydro-2-oxindole. (e) 2,4,6-trioxohexahydropyrimidine nucleus: For example, barbituric acid, 2-thiobarbituric acid, and derivatives thereof. Examples of the derivatives include 1-alkyl compounds such as 1-methyl and 1-ethyl, 1,3-dialkyl compounds such as 1,3-dimethyl, 1,3-diethyl, and 1,3-dibutyl, 1,3-diaryl compounds such as 1,3-diphenyl, 1,3-di(p-chlorophenyl), and 1,3-di(p-ethoxycarbonylphenyl), 1-alkyl-1-aryl compounds such as 1-ethyl-3-phenyl, and 1,3-diheteroaryl compounds such as 1,3-di(2-pyridyl). (f) 2-thio-2,4-thiazolidinedione nucleus: For example, rhodanine and derivatives thereof. Examples of the derivatives include 3-alkylrhodanines such as 3-methylrhodanine, 3-ethylrhodanine, and 3-allylrhodanine, 3-arylrhodanines such as 3-phenylrhodanine, and 3-heteroarylrhodanines such as 3-(2-pyridyl)rhodanine. (g) 2-thio-2,4-oxazolidinedione nucleus (2-thio-2,4-(3H,5H)-oxazoledione nucleus): for example, 3-ethyl-2-thio-2,4-oxazolidinedione. (h) thianaphthenone nucleus: for example, 3(2H)-thianaphthenone-1,1-dioxide. (i) 2-thio-2,5-thiazolidinedione nucleus: for example, 3-ethyl-2-thio-2,5-thiazolidinedione.(j) 2,4-thiazolidinedione nucleus: for example, 2,4-thiazolidinedione, 3-ethyl-2,4-thiazolidinedione, and 3-phenyl-2,4-thiazolidinedione. (k) thiazolin-4-one nucleus: for example, 4-thiazolinone and 2-ethyl-4-thiazolinone. (l) 2,4-imidazolidinedione (hydantoin) nucleus: for example, 2,4-imidazolidinedione and 3-ethyl-2,4-imidazolidinedione. (m) 2-thio-2,4-imidazolidinedione (2-thiohydantoin) nucleus: for example, 2-thio-2,4-imidazolidinedione and 3-ethyl-2-thio-2,4-imidazolidinedione. (n) Imidazolin-5-one nucleus: for example, 2-propylmercapto-2-imidazolin-5-one, etc. (o) 3,5-pyrazolidinedione nucleus: for example, 1,2-diphenyl-3,5-pyrazolidinedione and 1,2-dimethyl-3,5-pyrazolidinedione, etc. (p) Benzothiophen-3(2H)-one nucleus: for example, benzothiophen-3(2H)-one, oxobenzothiophen-3(2H)-one, and dioxobenzothiophen-3(2H)-one, etc. (q) Indanone nucleus: for example, 1-indanone, 3-phenyl-1-indanone, 3-methyl-1-indanone, 3,3-diphenyl-1-indanone, and 3,3-dimethyl-1-indanone, etc. (r) Benzofuran-3-(2H)-one nucleus: for example, benzofuran-3-(2H)-one, etc. (s) 2,2-dihydrophenalene-1,3-dione nucleus, etc.

[0063] In formula (A-1), W １ represents a sulfur atom, an oxygen atom, and ═NR Ｗ１ , or =CR Ｗ２ R Ｗ３ Represents R Ｗ１ represents a hydrogen atom or a substituent. １ is preferably an oxygen atom or a sulfur atom, more preferably an oxygen atom, in that the response speed has a better dependency on the electric field strength. Ｗ１ represents a hydrogen atom or a substituent. Examples of the substituent include the groups exemplified above as the substituent W. Ｗ２ and R Ｗ３ each independently represents a cyano group, —SO ２ RＷ４ , -COOR Ｗ５ , or -COR Ｗ６ Represents R Ｗ４ ~R Ｗ６ R each independently represent an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, or an aliphatic heterocyclic group which may have a substituent. The aliphatic hydrocarbon group is defined as above, and an aliphatic hydrocarbon group having 1 to 4 carbon atoms is preferred. The aromatic ring group is defined as above, and an aromatic hydrocarbon group is preferred, and a phenyl group is more preferred. The aliphatic heterocyclic group is defined as above, and the heteroatom contained in the aliphatic heterocyclic group is preferably a sulfur atom, an oxygen atom, or a nitrogen atom. R Ｗ４ ~R Ｗ６ Examples of the substituent that each group represented by the following formula may have include the substituents exemplified for the substituent W above.

[0064] In formula (A-1), * represents a bonding position.

[0065] The group represented by formula (A-1) is preferably a group represented by formula (A-3) in that the effects of the present invention are more excellent.

[0066]

[0067] In formula (A-3), C ２ represents a ring containing at least three carbon atoms, which may have a substituent. ２The three carbon atoms contained in are the three carbon atoms specified in formula (A-3). The number of carbon atoms in the ring is preferably 3 to 30, more preferably 3 to 20, and even more preferably 3 to 10. The number of carbon atoms in the ring is the number including the three carbon atoms specified in the formula. The ring may be either an aromatic ring or a non-aromatic ring. The ring may be either a monocyclic or polycyclic ring, and is preferably a 5-membered ring, a 6-membered ring, or a fused ring containing at least one of a 5-membered ring and a 6-membered ring. The number of carbon atoms in the fused ring containing at least one of a 5-membered ring and a 6-membered ring is preferably 6 to 20, more preferably 6 to 15, and even more preferably 8 to 10. The ring may have a heteroatom. Examples of the heteroatom include a nitrogen atom, a sulfur atom, an oxygen atom, a selenium atom, a tellurium atom, a phosphorus atom, a silicon atom, and a boron atom, and a sulfur atom, a nitrogen atom, or an oxygen atom is preferred. The number of heteroatoms contained in the ring is preferably 0 to 10, and more preferably 0 to 5. ２ Among the carbon atoms constituting the ring represented by the formula (A-2), the carbon atom at the bonding position marked with * and W ２ Or W ３ A carbon atom other than the carbon atom bonded to the ring C may be substituted with a carbonyl carbon (>C=O) or a thiocarbonyl carbon (>C=S), etc. １ The substituents are the same as those that may be possessed by the group.

[0068] In formula (A-3), W ２ and W ３ are each independently a sulfur atom, an oxygen atom, or ═NR Ｗ１ , or =CR Ｗ２ R Ｗ３ In terms of achieving better effects of the present invention, an oxygen atom or a sulfur atom is preferred, and an oxygen atom is more preferred. Ｗ１ ~R Ｗ３ is as described above.

[0069] The group represented by formula (A-3) is more preferably a group represented by formula (C-1) or a group represented by formula (C-2).

[0070]

[0071] In formula (C-1), X ｃ１ and X ｃ２ Each of X independently represents an oxygen atom or a sulfur atom. ｃ１ and X ｃ２ is preferably an oxygen atom, and X ｃ１ and X ｃ２ is more preferably an oxygen atom.

[0072] In formula (C-1), C ３ represents an aromatic ring which may have a substituent. The aromatic ring may be either a monocyclic or polycyclic ring. The number of ring members in the aromatic ring is preferably 4 to 30, more preferably 5 to 12, and even more preferably 5 to 8. The number of ring members in the aromatic ring is the number including the two carbon atoms specified in the formula. The aromatic ring may be either an aromatic hydrocarbon ring or an aromatic heterocyclic ring, with an aromatic hydrocarbon ring being preferred. Specific examples of the aromatic ring are as described above, with a benzene ring, a naphthalene ring, an anthracene ring, a pyrene ring, a thiophene ring, a furan ring, a thiazole ring, an oxazole ring, a pyridine ring, a thienothiophene ring, a benzothiophene ring, a benzofuran ring, a pyrazine ring, a pyrimidine ring, or a pyridazine ring being preferred, a benzene ring, a naphthalene ring, or a thiophene ring being more preferred, and a benzene ring being even more preferred. Examples of the substituent that the aromatic ring may have include the groups exemplified by the substituent W above, with an alkyl group or a halogen atom being preferred. The number of substituents that the aromatic ring may have is not particularly limited, but is preferably 0 to 8, and more preferably 0 to 4.

[0073] In formula (C-2), X ｃ３ ~X ｃ５ Each of X independently represents an oxygen atom or a sulfur atom. ｃ３ and X ｃ４ is preferably an oxygen atom, and X ｃ３ ~X ｃ５ is more preferably an oxygen atom.

[0074] Z ａ１ and Z ａ２ are each independently -NR ｃ１- or - C(R ｃ２ R ｃ３ )-, and the effect of the present invention is more excellent. ｃ１ - is preferred. ｃ１ ~R ｃ３ each independently represents a hydrogen atom or a substituent. Examples of the substituent include the groups exemplified by the substituent W above, with an alkyl group or an aryl group being preferred, and an alkyl group being more preferred. The alkyl group may be linear, branched, or cyclic, with a linear group being preferred. The alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 6, even more preferably 1 to 3, and particularly preferably 1 or 2. The aryl group may be monocyclic or polycyclic, with a phenyl group being preferred. The aryl group may further have a substituent, and examples of the substituent include the groups exemplified by the substituent W above.

[0075] In formula (A-2), R Ａ１ and R Ａ２ each independently represents a cyano group, —SO ２ R Ｚ１ , -COOR Ｚ２ , or -COR Ｚ３ represents a cyano group or —COOR Ｚ２ is preferred. Ｚ１ ~R Ｚ３ R each independently represents an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, or an aliphatic heterocyclic group which may have a substituent. Ｚ１ ~R Ｚ３ The definitions and preferred embodiments of each group represented by R Ｗ４ ~R Ｗ６ is the same as the group represented by R Ｚ１ ~R Ｚ３ Among these, an aliphatic hydrocarbon group having 1 to 4 carbon atoms or a phenyl group is preferred.

[0076] In formula (A-2), * represents a bonding position.

[0077] Specific examples of the specific compounds are shown below, but the present invention is not limited to these. In the following structures, TMS represents a trimethylsilyl group.

[0078]

[0079]

[0080]

[0081] In the specific compounds exemplified above, each A independently represents one of the following groups: Two A's may be the same or different.

[0082]

[0083]

[0084]

[0085]

[0086] The molecular weight of the specific compound is preferably 400 to 1200, more preferably 450 to 1000, and even more preferably 450 to 900. When the molecular weight is within the above range, the sublimation temperature of the specific compound is lowered, and it is presumed that the specific compound has excellent suitability for production.

[0087] The specific compound preferably has an ionization potential of −5.0 to −6.0 eV in a single film from the viewpoints of stability when used as a p-type organic semiconductor and matching of the energy level with an n-type organic semiconductor.

[0088] The maximum absorption wavelength of the specific compound is preferably in the wavelength range of 450 to 800 nm, more preferably in the range of 500 to 650 nm. The maximum absorption wavelength is a value measured in a solution state (solvent: chloroform) after adjusting the absorption spectrum of the specific compound to a concentration such that the absorbance is 0.5 to 1.0. However, if the specific compound is insoluble in chloroform, the maximum absorption wavelength of the specific compound is determined by evaporating the specific compound and measuring the value using the specific compound in a film state.

[0089] The specific compound is particularly useful as a material for a photoelectric conversion film used in an imaging device, an optical sensor, or a photovoltaic cell. The specific compound often functions as a dye in the photoelectric conversion film. The specific compound can also be used as a coloring material, a liquid crystal material, an organic semiconductor material, a charge transport material, a pharmaceutical material, and a fluorescent diagnostic material.

[0090] The specific compound may be purified as necessary. Examples of methods for purifying the specific compound include sublimation purification, purification using silica gel column chromatography, purification using gel permeation chromatography, reslurry washing, reprecipitation purification, purification using an adsorbent such as activated carbon, and recrystallization purification.

[0091] The content of the specific compound in the photoelectric conversion film (=film thickness of the specific compound in terms of a single layer / film thickness of the photoelectric conversion film × 100) is not particularly limited, but is preferably 5 to 75% by volume, more preferably 10 to 50% by volume, and even more preferably 15 to 40% by volume. Only one type of specific compound may be used, or two or more types may be used. When two or more types are used, it is preferable that the total amount thereof is in the above range.

[0092] <n-Type Organic Semiconductor> The photoelectric conversion film preferably contains an n-type organic semiconductor in addition to the specific compound. The n-type organic semiconductor is a compound different from the specific compound. The n-type organic semiconductor is an acceptor organic semiconductor material (compound) and refers to an organic compound that has the property of easily accepting electrons. In other words, the n-type organic semiconductor refers to the organic compound that has a larger electron affinity when two organic compounds are used in contact with each other. In other words, any organic compound can be used as the acceptor organic semiconductor as long as it is an organic compound with electron-accepting properties. Examples of n-type organic semiconductors include fullerenes selected from the group consisting of fullerenes and derivatives thereof; fused aromatic carbon ring compounds (e.g., naphthalene derivatives, anthracene derivatives, phenanthrene derivatives, tetracene derivatives, pyrene derivatives, perylene derivatives, and fluoranthene derivatives); 5- to 7-membered heterocyclic compounds having at least one selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom (e.g., pyridine, pyrazine, pyrimidine, pyridazine, triazine, quinoline, quinoxaline, quinazoline, phthalazine, cinnoline, isoquinoline, pteridine, acridine, phenazine, phenanthroline, tetrazole, pyrazole, imidazole, and thiazole). ), polyarylene compounds; fluorene compounds; cyclopentadiene compounds; silyl compounds; 1,4,5,8-naphthalenetetracarboxylic dianhydride; 1,4,5,8-naphthalenetetracarboxylic diimide derivatives; anthraquinodimethane derivatives; diphenylquinone derivatives; bathocuproine, bathophenanthroline, and derivatives thereof; triazole compounds; distyrylarylene derivatives; metal complexes having a nitrogen-containing heterocyclic compound as a ligand; silole compounds; 3,4,9,10-perylenetetracarboxylic dianhydride; 3,4,9,10-perylenetetracarboxylic diimide derivatives; and the compounds described in paragraphs

[0056] to

[0057] of JP-A No. 2006-100767.

[0093] As the n-type organic semiconductor (compound), fullerenes selected from the group consisting of fullerenes and derivatives thereof are preferred. For example, fullerene C ６０ , fullerene C ７０, fullerene C ７６ , fullerene C ７８ , fullerene C ８０ , fullerene C ８２ , fullerene C ８４ , fullerene C ９０ , fullerene C ９６ , fullerene C ２４０ , fullerene C ５４０ and mixed fullerenes. Examples of fullerene derivatives include compounds in which a substituent is added to the above-mentioned fullerenes. The substituent is preferably an alkyl group, an aryl group, or a heterocyclic group. Preferred fullerene derivatives are the compounds described in JP-A-2007-123707.

[0094] The molecular weight of the n-type organic semiconductor is preferably 200 to 1,200, more preferably 200 to 900.

[0095] The maximum absorption wavelength of the n-type organic semiconductor is preferably 400 nm or less or in the range of 500 to 600 nm.

[0096] The photoelectric conversion film preferably has a bulk heterostructure formed in a state in which a specific compound and an n-type organic semiconductor are mixed. The bulk heterostructure is a layer in the photoelectric conversion film in which a specific compound and an n-type organic semiconductor are mixed and dispersed. The photoelectric conversion film having a bulk heterostructure can be formed by either a wet method or a dry method. The bulk heterostructure is described in detail in paragraphs

[0013] to

[0014] of JP 2005-303266 A.

[0097] The difference in electron affinity between the specific compound and the n-type organic semiconductor is preferably 0.1 eV or more.

[0098] When the photoelectric conversion film contains an n-type organic semiconductor, the content of the n-type organic semiconductor in the photoelectric conversion film (thickness of the n-type organic semiconductor in terms of a single layer / thickness of the photoelectric conversion film × 100) is preferably 15 to 75 vol%, more preferably 20 to 60 vol%, and still more preferably 20 to 50 vol%.

[0099] When the n-type organic semiconductor contains fullerenes, the content of the fullerenes relative to the total content of the n-type organic semiconductors (film thickness of fullerenes converted into a single layer / total film thickness of each n-type organic semiconductor converted into a single layer × 100) is preferably 50 to 100% by volume, more preferably 80 to 100% by volume. Fullerenes may be used singly or in combination of two or more types.

[0100] In terms of the response speed of the photoelectric conversion element, the content of the specific compound relative to the total content of the specific compound and the n-type organic semiconductor (film thickness in monolayer equivalent of the specific compound / (film thickness in monolayer equivalent of the specific compound + film thickness in monolayer equivalent of the n-type organic semiconductor) x 100) is preferably 20 to 80% by volume, more preferably 40 to 80% by volume. When the photoelectric conversion film contains an n-type organic semiconductor and a p-type organic semiconductor, the content of the specific compound (film thickness in monolayer equivalent of the specific compound / (film thickness in monolayer equivalent of the specific compound + film thickness in monolayer equivalent of the n-type organic semiconductor + film thickness in monolayer equivalent of the p-type organic semiconductor) x 100) is preferably 10 to 75% by volume, more preferably 15 to 50% by volume. It is preferable that the photoelectric conversion film is substantially composed of the specific compound, the n-type organic semiconductor, and a p-type organic semiconductor that is included as desired. "Substantially" means that the total content of the specific compound, n-type organic semiconductor, and p-type organic semiconductor is 90 to 100% by volume, preferably 95 to 100% by volume, and more preferably 99 to 100% by volume, relative to the total volume of the photoelectric conversion film.

[0101] <p-Type Organic Semiconductor> The photoelectric conversion film preferably contains a p-type organic semiconductor in addition to the specific compound. The p-type organic semiconductor is a compound different from the specific compound. The p-type organic semiconductor is a donor organic semiconductor material (compound) and refers to an organic compound that has the property of easily donating electrons. In other words, the p-type organic semiconductor refers to the organic compound that has a smaller ionization potential when two organic compounds are used in contact with each other. The p-type organic semiconductor may be used alone or in combination of two or more types.

[0102] Examples of p-type organic semiconductors include triarylamine compounds (e.g., N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD), 4,4'-bis[N-(naphthyl)-N-phenyl-amino]biphenyl (α-NPD), compounds described in paragraphs

[0128] to

[0148] of JP-A No. 2011-228614, compounds described in paragraphs

[0052] to

[0063] of JP-A No. 2011-176259, compounds described in paragraphs

[0119] to

[0158] of JP-A No. 2011-225544, compounds, compounds described in paragraphs

[0044] to

[0051] of JP-A No. 2015-153910, and compounds described in paragraphs

[0086] to

[0090] of JP-A No. 2012-094660, etc.), pyrazoline compounds, styrylamine compounds, hydrazone compounds, polysilane compounds, thiophene compounds (for example, thienothiophene derivatives, dibenzothiophene derivatives, benzodithiophene derivatives, dithienothiophene derivatives, [1]benzothieno[3,2-b][1]benzothiophene (BTBT) derivatives, thieno[3,2-f:4,5-f']bis[1] Benzothiophene (TBBT) derivatives, compounds described in paragraphs

[0031] to

[0036] of JP2018-014474A, compounds described in paragraphs

[0043] to

[0045] of WO2016 / 194630A, compounds described in paragraphs

[0025] to

[0037] and

[0099] to

[0109] of WO2017 / 159684A, compounds described in paragraphs

[0029] to

[0034] of JP2017-076766A, compounds described in paragraphs

[0015] to

[0025] of WO2018 / 207722A, and compounds described in paragraph [00 45] to

[0053] , compounds described in paragraphs

[0045] to

[0055] of WO2019 / 058995, compounds described in paragraphs

[0063] to

[0089] of WO2019 / 081416, compounds described in paragraphs

[0033] to

[0036] of JP2019-80052A, compounds described in paragraphs

[0044] to

[0054] of WO2019 / 054125, compounds described in paragraphs

[0041] to

[0046] of WO2019 / 093188, compounds described in paragraphs

[0034] to

[0037] of JP2019-050398A,Compounds described in paragraphs

[0033] to

[0036] of JP-A No. 2018-206878, compounds described in paragraph

[0038] of JP-A No. 2018-190755, compounds described in paragraphs

[0019] to

[0021] of JP-A No. 2018-026559, compounds described in paragraphs

[0031] to

[0056] of JP-A No. 2018-170487, compounds described in paragraphs

[0036] to

[0041] of JP-A No. 2018-166200 Compounds described in paragraphs

[0055] to

[0082] of JP-A No. 2018-113425, compounds described in paragraphs

[0041] to

[0050] of JP-A No. 2018-113425, compounds described in paragraphs

[0044] to

[0048] of JP-A No. 2018-085430, compounds described in paragraphs

[0041] to

[0045] of JP-A No. 2018-056546, compounds described in paragraphs

[0042] to

[0049] of JP-A No. 2018-046267, and paragraphs of JP-A No. 2018-014474

[0031] to

[0036] compounds described in paragraphs

[0036] to

[0046] of WO2018 / 016465, and compounds described in paragraphs

[0045] to

[0048] of JP-A-2020-010024, etc.), cyanine compounds, oxonol compounds, polyamine compounds, indole compounds, pyrrole compounds, pyrazole compounds, polyarylene compounds, fused aromatic carbocyclic compounds (e.g., naphthalene derivatives, anthracene derivatives, phenanthrene derivatives, tetracene derivatives, pentacene derivatives, pyrene derivatives, perylene derivatives, and fluoranthene derivatives), porphyrin compounds, phthalocyanine compounds, triazole compounds, oxadiazole compounds, imidazole compounds, polyarylalkane compounds, pyrazolone compounds, amino-substituted chalcone compounds, oxazole compounds, fluorenone compounds, silazane compounds, and metal complexes having a nitrogen-containing heterocyclic compound as a ligand. Examples of p-type organic semiconductors include benzoxazole compounds (for example, compounds described in Figures 3 to 7 of JP-A-2022-123944), dicarbazole compounds (for example, compounds described in Figures 2 to 5 of JP-A-2022-122839), benzoquinazoline compounds (for example, compounds described in paragraphs

[0053] to

[0056] of JP-A-2022-120323),Azine compounds (for example, compounds described in paragraphs

[0041] to

[0042] of JP-A No. 2022-120273), compounds described in Figures 2 to 10 of JP-A No. 2022-115832, indolotriphenylene compounds (for example, compounds described in paragraphs

[0065] to

[0072] of JP-A No. 2022-108268), indolocarbazole compounds (for example, compounds described in paragraphs

[0052] to [00 73] and the compounds described in paragraph

[0028] of JP-A No. 2022-100258), triscarbazolylphenyl compounds (for example, the compounds described in paragraphs

[0038] to

[0040] of JP-A No. 2022-181226), the compounds described in paragraphs

[0070] to

[0082] of JP-A No. 2022-027575, and the compounds described in paragraphs

[0051] to

[0064] of JP-A No. 2021-163968. Examples of p-type organic semiconductors include compounds having a smaller ionization potential than n-type organic semiconductors, and if this condition is met, the organic dyes exemplified as n-type organic semiconductors can be used. Examples of compounds that can be used as p-type organic semiconductor compounds are listed below.

[0103]

[0104]

[0105]

[0106]

[0107] The difference in ionization potential between the specific compound and the p-type organic semiconductor is preferably 0.1 eV or more.

[0108] When the photoelectric conversion film contains a p-type organic semiconductor, the content of the p-type organic semiconductor in the photoelectric conversion film (thickness of the p-type organic semiconductor in terms of a single layer / thickness of the photoelectric conversion film × 100) is preferably 15 to 75 vol%, more preferably 20 to 60 vol%, and still more preferably 25 to 50 vol%.

[0109] The photoelectric conversion film containing the specific compound is a non-luminescent film and has characteristics different from those of an organic electroluminescent device (OLED: Organic Light Emitting Diode). A non-luminescent film means a film having a luminescence quantum efficiency of 1% or less, preferably 0.5% or less, more preferably 0.1% or less. The lower limit is often 0% or more.

[0110] <Dye> The photoelectric conversion film preferably contains a dye in addition to the specific compound. The dye is a compound different from the specific compound. The dye is preferably an organic dye. Examples of the organic dye include cyanine dyes, styryl dyes, hemicyanine dyes, merocyanine dyes (including zeromethine merocyanine (simple merocyanine)), rhodacyanine dyes, allopolar dyes, oxonol dyes, hemioxonol dyes, squarylium dyes, croconium dyes, azamethine dyes, coumarin dyes, arylidene dyes, anthraquinone dyes, triphenylmethane dyes, azo dyes, azomethine dyes, metallocene dyes, fluorenone dyes, fulgide dyes, perylene dyes, phenazine dyes, phenothiazine dyes, quinone dyes, diphenylmethane dyes, polyene dyes, acridine dyes, and acrylonitrile dyes. Examples of the organic dye include lysinone dyes, diphenylamine dyes, quinophthalone dyes, phenoxazine dyes, phthaloperylene dyes, dioxane dyes, porphyrin dyes, chlorophyll dyes, phthalocyanine dyes, subphthalocyanine dyes, metal complex dyes, imidazoquinoxaline dyes described in WO 2020 / 013246, WO 2022 / 168856, JP 2023-010305 A, and JP 2023-010299 A, as well as acceptor-donor-acceptor type dyes in which two acidic nuclei are bonded to a donor, and donor-acceptor-donor type dyes in which two donors are bonded to an acceptor. Of these, acceptor-donor-acceptor type dyes are preferred as organic dyes.

[0111] The maximum absorption wavelength of the dye is preferably in the visible light region, more preferably in the wavelength range of 400 to 650 nm, and even more preferably in the wavelength range of 450 to 650 nm.

[0112] The content of the dye relative to the total content of the specific compound and the dye in the photoelectric conversion film (= (film thickness of the dye in terms of a single layer / (film thickness of the specific compound in terms of a single layer+film thickness of the dye in terms of a single layer)×100)) is preferably 5 to 75 vol%, more preferably 5 to 60 vol%, and still more preferably 5 to 50 vol%.

[0113] <Film formation method> Examples of the film formation method for the photoelectric conversion film include dry film formation methods. Examples of dry film formation methods include physical vapor deposition methods such as vapor deposition (particularly vacuum deposition), sputtering, ion plating, and MBE (Molecular Beam Epitaxy), as well as CVD (Chemical Vapor Deposition) methods such as plasma polymerization, and vacuum deposition methods are preferred. When forming the photoelectric conversion film by vacuum deposition, manufacturing conditions such as the degree of vacuum and deposition temperature can be set according to conventional methods.

[0114] The thickness of the photoelectric conversion film is preferably from 10 to 1,000 nm, more preferably from 50 to 800 nm, and even more preferably from 50 to 500 nm.

[0115] [Electrodes] The photoelectric conversion element preferably has electrodes. The electrodes (upper electrode (transparent conductive film) 15 and lower electrode (conductive film) 11) are made of a conductive material. Examples of conductive materials include metals, alloys, metal oxides, electrically conductive compounds, and mixtures thereof. Since light is incident through the upper electrode 15, it is preferable that the upper electrode 15 is transparent to the light to be detected. Examples of materials constituting the upper electrode 15 include conductive metal oxides such as tin oxide doped with antimony or fluorine (ATO: Antimony Tin Oxide, FTO: Fluorine-doped Tin Oxide), tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO: Indium Tin Oxide), and indium zinc oxide (IZO); metal thin films such as gold, silver, chromium, and nickel; mixtures or laminates of these metals and conductive metal oxides; and organic conductive materials such as polyaniline, polythiophene, and polypyrrole; and nanocarbon materials such as carbon nanotubes and graphene. Of these, conductive metal oxides are preferred in terms of high conductivity and transparency.

[0116] Typically, when the conductive film is made thinner than a certain range, the resistance value often increases rapidly. In a solid-state imaging device incorporating a photoelectric conversion element according to this embodiment, the sheet resistance may be 100 to 10,000 Ω / □, and there is a wide degree of freedom in the range of film thickness that can be reduced. Furthermore, the thinner the upper electrode (transparent conductive film) 15, the less light it absorbs, and generally the higher the light transmittance. An increase in light transmittance is desirable because it increases light absorption in the photoelectric conversion film and enhances photoelectric conversion performance. Considering the suppression of leakage current, the increase in the resistance value of the thin film, and the increase in transmittance that accompany a reduction in film thickness, the thickness of the upper electrode 15 is preferably 5 to 100 nm, and more preferably 5 to 20 nm.

[0117] Depending on the application, the lower electrode 11 may be made transparent or may be made non-transparent and reflect light. Examples of materials constituting the lower electrode 11 include conductive metal oxides such as tin oxide (ATO, FTO) doped with antimony or fluorine, tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); metals such as gold, silver, chromium, nickel, titanium, tungsten, and aluminum; conductive compounds such as oxides or nitrides of these metals (e.g., titanium nitride (TiN)); mixtures or laminates of these metals and conductive metal oxides; organic conductive materials such as polyaniline, polythiophene, and polypyrrole; and carbon materials such as carbon nanotubes and graphene.

[0118] The method for forming the electrodes can be appropriately selected depending on the electrode material. Specific examples include wet methods such as printing and coating; physical methods such as vacuum deposition, sputtering, and ion plating; and chemical methods such as CVD and plasma CVD. When the electrode material is ITO, examples include electron beam methods, sputtering, resistance heating deposition, chemical reaction methods (such as the sol-gel method), and coating of a dispersion of indium tin oxide.

[0119] [Charge-blocking film: electron-blocking film, hole-blocking film] The photoelectric conversion element preferably has one or more intermediate layers in addition to the photoelectric conversion film between the conductive film and the transparent conductive film. Examples of the intermediate layer include a charge-blocking film. When the photoelectric conversion element has this film, the properties (quantum efficiency, response speed, etc.) of the resulting photoelectric conversion element are more excellent. Examples of the charge-blocking film include an electron-blocking film and a hole-blocking film.

[0120] <Electron Blocking Film> The electron blocking film is a donor organic semiconductor material (compound), and the above-mentioned p-type organic semiconductor can be used. Polymer materials can also be used as the electron blocking film. Examples of polymer materials include polymers of phenylene vinylene, fluorene, carbazole, indole, pyrene, pyrrole, picoline, thiophene, acetylene, and diacetylene, as well as derivatives thereof.

[0121] The electron blocking film may be composed of multiple films. The electron blocking film may be composed of an inorganic material. In general, inorganic materials have a higher dielectric constant than organic materials, so when an inorganic material is used for the electron blocking film, a higher voltage is applied to the photoelectric conversion film, resulting in higher quantum efficiency. Examples of inorganic materials that can be used for the electron blocking film include calcium oxide, chromium oxide, chromium copper oxide, manganese oxide, cobalt oxide, nickel oxide, copper oxide, gallium copper oxide, strontium copper oxide, niobium oxide, molybdenum oxide, indium copper oxide, indium silver oxide, and iridium oxide.

[0122] <Hole-Blocking Film> The hole-blocking film is an acceptor organic semiconductor material (compound), and the n-type organic semiconductors described above can be used. The hole-blocking film may be composed of multiple films.

[0123] Examples of methods for producing a charge blocking film include dry film formation and wet film formation. Examples of dry film formation methods include vapor deposition and sputtering. Vapor deposition may be either physical vapor deposition (PVD) or chemical vapor deposition (CVD), with physical vapor deposition such as vacuum deposition being preferred. Examples of wet film formation methods include inkjet printing, spray printing, nozzle printing, spin coating, dip coating, casting, die coating, roll coating, bar coating, and gravure coating, with the inkjet method being preferred in terms of high-precision patterning.

[0124] The thickness of each of the charge blocking films (electron blocking film and hole blocking film) is preferably from 3 to 200 nm, more preferably from 5 to 100 nm, and even more preferably from 5 to 30 nm.

[0125] [Substrate] The photoelectric conversion element may further include a substrate. Examples of the substrate include a semiconductor substrate, a glass substrate, and a plastic substrate. The substrate is usually positioned such that a conductive film, a photoelectric conversion film, and a transparent conductive film are stacked in this order on the substrate.

[0126] [Sealing Layer] The photoelectric conversion element may further have a sealing layer. The performance of photoelectric conversion materials may be significantly degraded in the presence of degrading factors such as water molecules. Therefore, the degradation can be prevented by covering and sealing the entire photoelectric conversion film with a sealing layer made of ceramics such as dense metal oxides, metal nitrides, or metal nitride oxides, or diamond-like carbon (DLC), which do not allow water molecules to penetrate. Examples of sealing layers include those described in paragraphs

[0210] to

[0215] of JP 2011-082508 A, the contents of which are incorporated herein by reference.

[0127] [Method for manufacturing photoelectric conversion element] Examples of methods for manufacturing photoelectric conversion elements include known manufacturing methods. Specifically, for example, methods for manufacturing photoelectric conversion elements include a step of forming a conductive film on a substrate, a step of forming a photoelectric conversion film, and a step of forming a transparent conductive film. The method for manufacturing a photoelectric conversion element may include other steps (for example, a step of forming a charge blocking film and a step of forming a sealing layer) in addition to the above. The method for forming each layer is as described above.

[0128] [Imaging element] An example of an application of a photoelectric conversion element is an imaging element. An imaging element is an element that converts the optical information of an image into an electrical signal, and typically has multiple photoelectric conversion elements arranged in a matrix on the same plane, converting the optical signal into an electrical signal at each photoelectric conversion element (pixel), and outputting the electrical signal pixel by pixel sequentially to the outside of the imaging element. For this reason, each pixel is composed of one or more photoelectric conversion elements and one or more transistors. A manufacturing method for an imaging element is not particularly limited, but examples include a method including the step of manufacturing the photoelectric conversion element described above.

[0129] [Optical Sensor] Other applications of the photoelectric conversion element include, for example, a photocell and an optical sensor, and the photoelectric conversion element of the present invention is preferably used as an optical sensor. As an optical sensor, the photoelectric conversion element may be used alone, or may be used as a line sensor in which the photoelectric conversion elements are arranged linearly or as a two-dimensional sensor in which the photoelectric conversion elements are arranged planarly.

[0130] [Compound] The present invention also includes inventions of specific compounds.

[0131] The present invention will be described in more detail below with reference to the following examples. The materials, amounts used, ratios, treatment details, treatment procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the following examples.

[0132] [Compounds used in photoelectric conversion film] The materials used in the photoelectric conversion film are shown below.

[0133] [Synthesis of Compound D-1] Compound D-1 was synthesized according to the following scheme.

[0134]

[0135] Synthesis of Compound (D-1-3) Compound (D-1-1) (2.7 g, 12.8 mmol), compound (D-1-2) (4.9 g, 14.0 mmol), tripotassium phosphate (5.4 g, 25.5 mmol), THF (tetrahydrofuran, 54 mL), and water (11 mL) were mixed and degassed under vacuum. Then, bis(triphenylphosphine)palladium(II) dichloride (443 mg, 0.38 mmol) was added and the mixture was stirred at 70°C for 4 hours. The mixture was allowed to cool to room temperature and diluted with ethyl acetate. The aqueous layer was removed using a separatory funnel, and the resulting organic layer was dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The resulting crude product was purified by silica gel chromatography (eluent (volume ratio): hexane / ethyl acetate = 3 / 1) to obtain compound (D-1-3) (4.8 g, 89%).

[0136] <Synthesis of Compound (D-1-4)> Compound (D-1-3) (4.8 g, 11.4 mmol) and ethylene glycol (96 mL) were mixed and stirred for 30 minutes at 160° C. The mixture was allowed to cool to room temperature, and the precipitated solid was collected by filtration to obtain compound (D-1-4) (3.1 g, 85%).

[0137] <Synthesis of Compound (D-1-5)> Compound (D-1-4) (3.0 g, 9.37 mmol), methyl p-toluenesulfonate (1.92 g, 10.3 mmol), cesium carbonate (6.11 g, 18.7 mmol), and DMF (N,N-dimethylformamide, 30 mL) were mixed and stirred at room temperature for 2 hours. Water was added to the reaction solution, and the mixture was stirred for 30 minutes. Then, the mixture was extracted with hexane / ethyl acetate (1 / 1) using a separatory funnel. The resulting organic layer was dried over magnesium sulfate, filtered, and concentrated under reduced pressure to obtain compound (D-1-5) (3.1 g, 99%).

[0138] Synthesis of Compound (D-1-6) Compound (D-1-5) (1.5 g, 4.49 mmol), a 0.6 M lanthanum(III) chloride bis(lithium chloride) complex solution in THF (8.2 mL, 4.94 mmol), and THF (15 mL) were mixed and stirred in an ice bath. To this mixture, a 1.0 M methylmagnesium bromide solution in THF (6.73 mL, 6.73 mmol) was slowly added dropwise, and the mixture was stirred in an ice bath for 30 minutes. A saturated aqueous ammonium chloride solution (15 mL) was slowly added to the resulting reaction solution, followed by addition of ethyl acetate (30 mL) and 1N hydrochloric acid (10 mL), and the mixture was stirred at room temperature for 10 minutes. The aqueous layer was removed using a separatory funnel, and the resulting organic layer was dried over magnesium sulfate, filtered, and concentrated under reduced pressure to obtain compound (D-1-6) (1.54 g, 98%).

[0139] <Synthesis of Compound (D-1-7)> Compound (D-1-6) (1.54 g, 4.40 mmol) and hexane (155 mL) were mixed, sulfuric acid (1.18 mL, 22.0 mmol) was added, and the mixture was stirred at room temperature for 6 hours. Water (50 mL) was added to the reaction solution, and the mixture was stirred at room temperature for 10 minutes. After that, a 1N aqueous sodium hydroxide solution (50 mL) was added, and the mixture was stirred at room temperature for an additional 1 hour. After extraction with dichloromethane using a separatory funnel, the obtained organic layer was dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained crude product was recrystallized from dichloromethane and methanol, and the precipitate was collected by filtration to obtain compound (D-1-7) (1.1 g, 75%).

[0140] <Synthesis of Compound (D-1-8)> Compound (D-1-7) (656 mg, 1.97 mmol) and THF (20 mL) were mixed and stirred at -78°C, and then 1.07 M lithium diisopropylamide in THF (5.53 mL, 5.92 mmol) was slowly added dropwise thereto, and the mixture was stirred at -78°C for 30 minutes. The reaction solution was stirred at -78°C, and then 1.51 M n-butyllithium solution in hexane (6.54 mL, 9.87 mmol) was slowly added dropwise thereto, and the mixture was stirred at -78°C for 2 hours. The reaction solution was stirred at -78°C, and then DMF (1.83 mL, 23.7 mmol) was slowly added dropwise thereto, and the mixture was stirred in an ice bath for 30 minutes. A saturated aqueous solution of ammonium chloride (20 mL) was slowly added to the reaction mixture, followed by stirring at room temperature for 15 minutes. The mixture was extracted with ethyl acetate using a separatory funnel, and the resulting organic layer was dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The resulting crude product was purified by silica gel chromatography (eluent (volume ratio): dichloromethane / ethyl acetate = 95 / 5) to obtain compound (D-1-8) (280 mg, 46%).

[0141] <Synthesis of Compound D-1> Compound (D-1-8) (200 mg, 0.65 mmol), compound (D-1-9) (242 mg, 1.42 mmol), and 1-butanol (10 mL) were mixed and stirred at 130°C for 2 hours. The mixture was allowed to cool to room temperature, and the precipitate was collected by filtration. The obtained crude product was recrystallized with dichloromethane and methanol, and the crude product obtained by collecting the precipitate by filtration was purified by sublimation to obtain Compound D-1 (295 mg, 74%). The structure of the obtained Compound D-1 was confirmed by NMR (Nuclear Magnetic Resonance). Compound D-1: １ H NMR (400 MHz, CDCl ３ ) 8.98 (0.7H, s), 8.92 (0.3H, s), 8.73 (1H, s), 8.72 (1H, s), 7.81-7.88 (1H, m), 7.76-7.79 ( 1H, m), 7.63 (1H, d), 4.04-4.15 (7H, m), 3.41-3.48 (6H, m), 1.66 (6H, s), 1.26-1.35 (6H, m)

[0142] The compounds used in the photoelectric conversion film of each of the Examples and Comparative Examples other than Compound D-1 were synthesized according to the synthesis method of Compound D-1.

[0143] [Specific Compounds] The specific compounds used in the photoelectric conversion film and comparative compounds for comparison are shown below, where compounds D-1 to D-22 are specific compounds and compounds C-1 to C-3 are comparative compounds.

[0144]

[0145]

[0146] [n-type organic semiconductor] C60: fullerene (C ６０ )

[0147] [p-type organic semiconductor]

[0148]

[0149] [Pigment]

[0150]

[0151] [Evaluation] Photoelectric conversion elements were fabricated using the above materials, and the following tests X and Y were carried out.

[0152] [Test X] A photoelectric conversion element was prepared as follows, and the quantum efficiency, response speed, and electric field strength dependency of the quantum efficiency when receiving green-red light (wavelength 600 nm) were evaluated.

[0153] <Preparation of Photoelectric Conversion Element> A photoelectric conversion element having the configuration shown in FIG. 2 was prepared using the various components shown above. Here, the photoelectric conversion element comprises a lower electrode 11, an electron blocking film 16A, a photoelectric conversion film 12, a hole blocking film 16B, and an upper electrode 15. Specifically, amorphous ITO was formed on a glass substrate by sputtering to form a lower electrode 11 (thickness: 30 nm), and compound (EB-1) was further formed on the lower electrode 11 by vacuum heating deposition to form an electron blocking film 16A (thickness: 30 nm). Subsequently, with the glass substrate at room temperature, each specific compound or each comparative compound shown in Table 1 and an n-type organic semiconductor (fullerene (C ６０)) and a p-type organic semiconductor (compound P-1) were co-deposited by vacuum deposition to form a film having a thickness of 80 nm in terms of a single layer. This resulted in a photoelectric conversion film 12 having a bulk heterostructure of 240 nm. At this time, the film formation rate of the photoelectric conversion film 12 was 1.0 Å / sec. Furthermore, compound (EB-2) was deposited on the photoelectric conversion film 12 to form a hole blocking film 16B (thickness: 10 nm). Amorphous ITO was deposited on the hole blocking film 16B by sputtering to form an upper electrode 15 (transparent conductive film) (thickness: 10 nm). After a SiO film was formed as a sealing layer on the upper electrode 15 by vacuum deposition, aluminum oxide (Al ２ O ３ The resulting laminate was heated in a glove box at 150° C. for 30 minutes to obtain a photoelectric conversion element.

[0154]

[0155] <Dark Current> The dark current of each of the obtained photoelectric conversion elements was measured by the following method. ５ A voltage was applied to the photoelectric conversion element so as to obtain an electric field strength of 50 nA / cm. The current value in a dark place (dark current) was measured. As a result, the dark current was 50 nA / cm for all the photoelectric conversion elements. ２ It was confirmed that the dark current was sufficiently low.

[0156] <Quantum Efficiency> The quantum efficiency of each photoelectric conversion element was measured when receiving green and red light by the following method. ５ After applying a voltage to achieve an electric field strength of 100 V / cm, light was irradiated from the upper electrode (transparent conductive film) side to evaluate the quantum efficiency (photoelectric conversion efficiency) at a wavelength of 600 nm, and the quantum efficiency (relative ratio) was calculated according to formula (S1). From the obtained value, the quantum efficiency was evaluated according to the following evaluation criteria. Example 1-1 was used as the reference example. The quantum efficiency is preferably rated C or higher. Formula (S1): Quantum efficiency (relative ratio) = (photoelectric conversion efficiency of each photoelectric conversion element) / (photoelectric conversion efficiency of the photoelectric conversion element of the reference example)

[0157] A: Quantum efficiency (relative ratio) is 0.95 or more. B: Quantum efficiency (relative ratio) is 0.80 or more and less than 0.95. C: Quantum efficiency (relative ratio) is 0.60 or more and less than 0.80. D: Quantum efficiency (relative ratio) is less than 0.60.

[0158] <Response Speed> The response speed of each photoelectric conversion element when receiving green and red light was evaluated by the following method. ５ A voltage was applied to the sample so that the intensity was 100 V / cm. Thereafter, an LED (light emitting diode) was momentarily turned on to irradiate light from the upper electrode (transparent conductive film) side, and the photocurrent at a wavelength of 600 nm at that time was measured with an oscilloscope to measure the rise time from 0% signal intensity to 97% signal intensity, and the relative response speed was calculated according to formula (S2). From the obtained value, the response speed was evaluated according to the following evaluation criteria. Example 1-1 was used as the reference example. The response speed is preferably rated B or higher. Formula (S2): Relative response speed = (rise time of each photoelectric conversion element) / (rise time of the photoelectric conversion element of the reference example)

[0159] A: Relative response speed is less than 1.1 B: Relative response speed is 1.1 or more and less than 1.5 C: Relative response speed is 1.5 or more

[0160] <Dependence of Quantum Efficiency on Electric Field Intensity> For each photoelectric conversion element, the dependence of quantum efficiency on electric field intensity when green and red light was received was evaluated by the following method. In the evaluation of the above <Quantum Efficiency>, the voltage applied to each photoelectric conversion element was 7.5×10 ４ The same procedure was followed except that the pressure was changed to 7.5 × 10 ４ The quantum efficiency (photoelectric conversion efficiency) at a wavelength of 600 nm of the photoelectric conversion element of Example 1-1 was measured. The electric field strength dependency of the quantum efficiency was calculated according to formula (S3), and the electric field strength dependency of the quantum efficiency was evaluated according to the following evaluation criteria. In formula (S3), the numerator and denominator are values ​​measured for the photoelectric conversion element of the same Example or Comparative Example. For example, in Example 1-1, the electric field strength of 7.5 × 10 at a wavelength of 600 nm of the photoelectric conversion element of Example 1-1 was ４V / cm and the electric field strength of 2.0×10 at a wavelength of 600 nm of the photoelectric conversion element of Example 1-1 ５ The quantum efficiency at an electric field strength of 7.5×10 V / cm is compared with the quantum efficiency at an electric field strength of 7.5×10 V / cm. The electric field strength dependency of the quantum efficiency is preferably rated as B or higher. Formula (S3): Electric field strength dependency of quantum efficiency = (electric field strength of each photoelectric conversion element 7.5×10 ４ V / cm) / (electric field strength of each photoelectric conversion element 2.0×10 ５ Quantum efficiency in V / cm

[0161] A: The electric field strength dependency of quantum efficiency is 0.9 or more. B: The electric field strength dependency of quantum efficiency is 0.8 or more and less than 0.9. C: The electric field strength dependency of quantum efficiency is less than 0.8.

[0162] [Results] The evaluation results are shown in Table 1 below. １ , A ２ " column indicates the specific compound. １ and A ２ represents a group represented by formula (A-1), it is represented as "A", and in other cases it is represented as "B". ３ " column is for specific compounds, X ３ represents a sulfur atom, it is represented as "A", and in other cases it is represented as "B". １ ~Y ４ " column indicates the Y １ ~Y ４ Ga-CR Ｙ１ In the table, "X" is used to indicate the difference between the two values. １ , X ２ " column is for specific compounds, X １ and X ２ But, -NR Ｘ１ -, -CR Ｘ２ R Ｘ３ - or -SiR Ｘ４ R Ｘ５ When it represents -, it is written as "A", and when it represents anything other than the above, it is written as "B".

[0163]

[0164] From the results shown in Table 1, it was confirmed that the photoelectric conversion element of the present invention has a small dependence of quantum efficiency on electric field strength when receiving green and red light, and is also excellent in quantum efficiency and response speed when receiving green and red light.

[0165] Comparison of Examples 1-10 to 1-13, 1-18 to 19, and 1-21 with other Examples reveals that X １ and X ２ But, -NR Ｘ１ -, -CR Ｘ２ R Ｘ３ - or -SiR Ｘ４ R Ｘ５ It was confirmed that when Y is -, the quantum efficiency is better and the dependence of the quantum efficiency on the electric field strength is smaller. １ ~Y ４ Ga-CR Ｙ１ It was confirmed that the response speed was superior when X = . From a comparison of Examples 1-15 to 1-16 and 1-19 to 1-20 with other Examples, ３ It was confirmed that when A is a sulfur atom, the response speed is superior. １ and A ２ It was confirmed that when is a group represented by formula (A-1), the quantum efficiency is better.

[0166] [Test Y] Each specific compound or each comparative compound, n-type organic semiconductor (fullerene (C ６０)), a p-type organic semiconductor (compound P-1), and any of the dyes (B-1) to (B-11) were co-deposited by vacuum deposition to form a photoelectric conversion film (film thickness 320 nm) using the specific compound or comparative compound: dye: p-type organic semiconductor: n-type organic semiconductor = 1:1:2:2 in terms of a single layer. Each photoelectric conversion element was prepared in the same manner as in [Test X], except that the photoelectric conversion elements prepared were evaluated in the same manner as in [Evaluation X], and the results were similar to those shown in Table 1. Specifically, for example, a photoelectric conversion element prepared according to the above method using compound D-1 showed evaluation results equivalent to those of Example 1 in Table 1. Note that photoelectric conversion elements were prepared for all combinations of each specific compound and each dye, and each evaluation was performed.

[0167] 10a, 10b Photoelectric conversion element 11 Conductive film (lower electrode) 12 Photoelectric conversion film 15 Transparent conductive film (upper electrode) 16A Electron blocking film 16B Hole blocking film

Claims

1. A photoelectric conversion element having a conductive film, a photoelectric conversion film, and a transparent conductive film in this order, wherein the photoelectric conversion film contains a compound represented by formula (1). In formula (1), X １ and X ２ each independently represents a sulfur atom, an oxygen atom, a selenium atom, or —NR Ｘ１ -, -CR Ｘ２ R Ｘ３ -, -SiR Ｘ４ R Ｘ５ - or -GeR Ｘ６ R Ｘ７ - represents X ３ represents a sulfur atom, an oxygen atom, a selenium atom, or —NR Ｘ１ - represents. Ｘ１ ~R Ｘ７ R each independently represents a hydrogen atom or a substituent. Ｘ２ and R Ｘ３ , R Ｘ４ and R Ｘ５ , and R Ｘ６ and R Ｘ７ may be bonded to each other to form a ring which may have a substituent. １ ~Y ４ are each independently -CR Ｙ１ = or represents a nitrogen atom. Ｙ１ represents a hydrogen atom or a substituent. １ and R ２ each independently represents a hydrogen atom or a substituent. １ and A ２ each independently represents a group represented by formula (A-1) or a group represented by formula (A-2). １ represents a ring containing two or more carbon atoms and which may have a substituent. １ represents a sulfur atom, an oxygen atom, and ═NR Ｗ１ , or =CR Ｗ２ R Ｗ３ Represents R Ｗ１ represents a hydrogen atom or a substituent. Ｗ２ and R Ｗ３ each independently represents a cyano group, —SO ２ R Ｗ４ , -COOR Ｗ５ , or -COR Ｗ６ Represents R Ｗ４ ~R Ｗ６ each independently represents an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, or an aliphatic heterocyclic group which may have a substituent. * represents a bonding position. In formula (A-2), R Ａ１ and R Ａ２ each independently represents a cyano group, —SO ２ R Ｚ１ , -COOR Ｚ２ , or -COR Ｚ３ Represents R Ｚ１ ~R Ｚ３ each independently represents an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, or an aliphatic heterocyclic group which may have a substituent. * represents a bonding position.

2. A １ and A ２ each independently represents a group represented by formula (A-1), 3. X ３ The photoelectric conversion element according to claim 1 , wherein represents a sulfur atom.

4. Y １ ~Y ４ are each independently -CR Ｙ１ The photoelectric conversion element according to claim 1 , wherein:

5. X １ and X ２ are each independently -NR Ｘ１ -, -CR Ｘ２ R Ｘ３ - or -SiR Ｘ４ R Ｘ５ The photoelectric conversion element according to any one of claims 1 to 4, wherein - represents.

6. The photoelectric conversion element according to any one of claims 1 to 4, wherein the photoelectric conversion film further contains an n-type organic semiconductor, and the photoelectric conversion film has a bulk heterostructure formed by mixing the compound represented by formula (1) with the n-type organic semiconductor.

7. The photoelectric conversion element according to claim 6, wherein the n-type organic semiconductor contains a fullerene selected from the group consisting of fullerenes and derivatives thereof.

8. The photoelectric conversion element according to any one of claims 1 to 4, wherein the photoelectric conversion film further contains a p-type organic semiconductor.

9. The photoelectric conversion element according to any one of claims 1 to 4, wherein the photoelectric conversion film further contains a dye.

10. The photoelectric conversion element according to any one of claims 1 to 4, further comprising one or more intermediate layers in addition to the photoelectric conversion film between the conductive film and the transparent conductive film.

11. An imaging device comprising the photoelectric conversion element according to any one of claims 1 to 4.

12. An optical sensor comprising the photoelectric conversion element according to any one of claims 1 to 4.

13. A method for manufacturing an imaging element, comprising the step of manufacturing the photoelectric conversion element according to any one of claims 1 to 4.

14. A compound represented by formula (1). In formula (1), X １ and X ２ each independently represents a sulfur atom, an oxygen atom, a selenium atom, or —NR Ｘ１ -, -CR Ｘ２ R Ｘ３ -, -SiR Ｘ４ R Ｘ５ - or -GeR Ｘ６ R Ｘ７ - represents X ３ represents a sulfur atom, an oxygen atom, a selenium atom, or —NR Ｘ１ - represents. Ｘ１ ~R Ｘ７ R each independently represents a hydrogen atom or a substituent. Ｘ２ and R Ｘ３ , R Ｘ４ and R Ｘ５ , and R Ｘ６ and R Ｘ７ may be bonded to each other to form a ring which may have a substituent. １ ~Y ４ are each independently -CR Ｙ１ = or represents a nitrogen atom. Ｙ１ represents a hydrogen atom or a substituent. １ and R ２ each independently represents a hydrogen atom or a substituent. １ and A ２ each independently represents a group represented by formula (A-1) or a group represented by formula (A-2). １ represents a ring containing two or more carbon atoms and which may have a substituent. １ represents a sulfur atom, an oxygen atom, and ═NR Ｗ１ , or =CR Ｗ２ R Ｗ３ Represents R Ｗ１ represents a hydrogen atom or a substituent. Ｗ２ and R Ｗ３ each independently represents a cyano group, —SO ２ R Ｗ４ , -COOR Ｗ５ , or -COR Ｗ６ Represents R Ｗ４ ~R Ｗ６ each independently represents an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, or an aliphatic heterocyclic group which may have a substituent. * represents a bonding position. In formula (A-2), R Ａ１ and R Ａ２ each independently represents a cyano group, —SO ２ R Ｚ１ , -COOR Ｚ２ , or -COR Ｚ３ Represents R Ｚ１ ~R Ｚ３ each independently represents an aliphatic hydrocarbon group which may have a substituent, an aromatic ring group which may have a substituent, or an aliphatic heterocyclic group which may have a substituent. * represents a bonding position.

15. A １ and A ２ each independently represents a group represented by formula (A-1).

16. X ３ 15. The compound of claim 14, wherein represents a sulfur atom.

17. Y １ ~Y ４ are each independently -CR Ｙ１ 15. The compound of claim 14, wherein:

18. X １ and X ２ are each independently -NR Ｘ１ -, -CR Ｘ２ R Ｘ３ - or -SiR Ｘ４ R Ｘ５ The compound according to any one of claims 14 to 17, wherein - represents.

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